CRU TS4.01 Precipitation
X axis: whole world in 720 0.50° steps,
first point at 179.75° W, last point at 179.75° E
Y axis: regular grid with 360 0.50° steps,
first point at 89.75° S, last point at 89.75° N

Monthly data available from Jan1901 to Dec2016 (1392 months)
Variable stn (stn) in Full metadata.
The associated land/sea mask is available for some operations